Survivor is a reality game show produced in many countries throughout the world. In the show, contestants are isolated in the wilderness and compete for cash and other prizes. The show uses a system of progressive elimination, allowing the contestants to vote off other tribe members until only one final contestant remains and wins the title of "Sole Survivor." The format for Survivor was created in 1992 by the British television producer Charlie Parsons for a United Kingdom TV production company called Planet 24, but the Swedish version, which debuted in 1997, was the first Survivor series to actually make it to television.

Survivor, through its seasons and various international versions, has maintained the basic premise of the game despite several new rules and gameplay twists introduced in later seasons. In the game, sixteen to twenty contestants, the castaways, are split into tribes and assigned separate camps at the filming's location, typically a tropical setting. As a tribe, the castaways must survive the elements, construct shelter, build fire, look for water, and scrounge for food and other necessities for the entire filming period, around 39 days. In the first half of the game, the tribes face off in challenges, some for rewards of food, shelter, or luxury items, while others are for immunity, preventing the winning tribe from having to go to the next Tribal Council. Tribes that do go to Tribal Council discuss the events of the last few days with the host asking questions, and then must vote out one of their own players, eliminating them from the game.

In the second half of the game, the tribes are merged into a single tribe. Challenges are played at an individual level for individual rewards and immunity. At subsequent Tribal Councils, those eliminated start to form the jury, who sit in on all subsequent Tribal Councils but otherwise do not participate. When only two or three castaways remain, those castaways attend a final Tribal Council, where the jury is given the opportunity to ask them questions. After this, the jury members then vote to decide which of the remaining castaways should be declared Sole Survivor.

The following description of the show is based primarily on the U.S. version of Survivor, though the general format applies to all international versions.

The tribe camp near the end of Survivor: Borneo. Tribes must build themselves basic shelters from natural resources and through reward items earned during the competition.

Players for each season are selected through applicants and casting calls, down-selecting to between sixteen and twenty players and additional alternates. U.S. version host Jeff Probst noted that while sixteen castaways makes it easier to split the tribes with respect to age and sex, they have used eighteen and twenty to provide them "wiggle room" in case of player injury or if one should want to quit the game.[1] These players undergo physical and psychological evaluation to make sure they are physically and mentally fit for the survival endurance and will not likely quit during the filming period, replacing those that are questionable with the alternates. In one case, Fiji, on the day before filming was to start after they had dismissed their alternates, one of the castaways opted out of the competition, forcing production to start with nineteen players and adapting the activities of the first few days to accommodate the odd number of players.[2]

Tribes may be pre-determined by production before filming starts. Often this is done to equalize the sexes and age ranges within both tribes. Other season have had the tribes separated by age, gender, or race. In other cases, the tribes may be created on the spot through schoolyard picks. Most often, only two tribes are featured, but some seasons have begun with three or four tribes. Once assigned a tribe, each castaway is given a buff in their tribe color to aid the viewers in identifying tribal alliance. Tribes are then subsequently given names, inspired by the local region, and directions to their camps.

At their camps, tribes are expected to build shelter against the elements from the local trees and other resources. Tribes are typically given minimal resources, such as a machete, water canteens, cooking pots, and staples of rice and grains, though this will vary from season to season. Sometimes, tribes will be provided a water well near the camp, but require the water to be boiled to make it potable, necessitating the need for the tribe to build fire. The tribes are encouraged to forage off the land for food, including fruits, wild animals, and fish.

In some seasons, a tribal swap will occur where one or more players will shift from one tribe to another. This may occur by random draw, schoolyard picks, or some other mechanism. When these occur, those players that shift tribes are given new buffs for their new tribe and return to that tribe's camp, with any personal possessions from their former camp moved with them. In Gabon, a tribal switch occurred twice. In seasons with more than two tribes, tribes may be merged down to two, or a tribe that has lost many members may be absorbed by the other remaining tribes. Once down to around half the remaining players, all remaining tribes are merged into one, usually allowing the players to select a new tribe name. In Palau, the Ulong tribe was whittled down to one castaway, so that instead of a normal merge, that player was absorbed into Koror. In Philippines, the Matsing tribe was absorbed by Tandang and Kalabaw tribes when it was down to two members.

Tribes compete frequently in both mental and physical challenges to win rewards or immunity, such as this race to pull cannons during the first episode of Survivor: Pearl Islands.

During both pre- and post-merge segments of filming, the castaways compete in a series of challenges. Tribes are alerted to these upcoming challenges by a message, often in rhyme, delivered to camp by the production team at a basket or box on a nearby tree; this message has come to be called "treemail", playing off the word "e-mail". The message typically hints at what the challenge might be. The message may also provide props to demonstrate this, practice equipment for the players, or a sampling of the reward.

Prior to the merge, tribes compete against each other in challenges. These most often are multi-segment obstacle courses that include both physical and mental elements with the tribe that finishes first declared the winner; commonly, these start with tribe members collecting puzzles pieces that are then used to solve a puzzle by other tribe members. Other challenges may be based on winning a number of rounds of head-to-head competitions. Challenges are normally held with equal numbers of all tribes participating and in some cases equal splits of gender. Tribes with more players will be asked to sit out as many players as needed to balance the numbers, with the stipulation that those players cannot sit out in back-to-back reward and immunity challenges.[3] When one tribe has more than twice the other tribe members, then players in the larger tribe cannot participate in back-to-back challenges. Tribes are given time to strategically decide who should sit out and who will perform the various duties on a challenge.

After the merge, challenges are generally performed on an individual basis. These include similar obstacle courses as for team challenges, but will often also include endurance challenges, having players maintain the balance under precarious situations for as long as possible, with the last player remaining winning the challenge. In some cases, during post-merge challenges, the individuals will be split into separate teams, with only the winning team eligible for reward or immunity.

Challenges can be played for rewards, immunity, or both. Rewards include food, survival equipment like flint, tarps, or fishing gear, luxury items, and short getaways from camp. Before the merge, the entire winning tribe will enjoy these rewards. Post-merge, only one player may win the reward but will be given the opportunity to select one or more other players to bring along with them on it. Individual challenge rewards may also include an advantage that can be used at the subsequent immunity challenge, such as advancing directly into the final round of the challenge without having to participate in the first round.

Immunity challenges provide the winning tribe or team with immunity from Tribal Council. Immunity is usually represented in a form of an idol prior to the merge, and a necklace afterwards. Prior to the merge, tribes with immunity do not attend Tribal Council, allowing them to stay intact. In seasons featuring more than two tribes, immunity will be available for all but the last place finishers, forcing this one tribe to Tribal Council. With individual immunity, those castaways still attend Tribal Council with the rest of the merged tribe, but, unless they assign immunity to someone else, are ineligible to be voted for. Winning immunity is only good for one Tribal Council; at the next immunity challenge, the tribe or castaway will be asked to give up the idol or necklace, making immunity "up for grabs". There have been a few cases in which individual immunity challenges have taken place prior to the merge whereupon usually one castaway in each tribe will be given immunity, after which both tribes will attend Tribal Council, one after the other. This is used to quickly dwindle the number of remaining castaways.

Though a wide variety of challenges have been used across the Survivor‍ '​s broadcast, several challenges are frequently reused:

A food eating challenge, involving food items that may be local delicacies but are considered gross or revolting by the castaways.

A trivia or "know your tribe" quiz, where castaways who provide correct answers are allowed to knock other castaways out of the challenge and prevent them from winning.

A "Survivor Auction", used in place of a reward challenge, in which the players are given a sum of money to use to bid on food items (both known and unknown at the time of bidding), other momentary luxuries like a bath, or advantages in the game, such as a clue to a hidden immunity idol or an advantage in the upcoming immunity challenge.

A "Loved Ones" challenge, where a spouse, parent, sibling, adult child or friend of each castaway has been brought to the location to participate in the challenge with their castaway. The winner typically gets to spend more time with their loved one either on a brief trip or back at camp.

A "Second Chance" challenge, where elements of previous challenges are reused in a single course.

The final immunity challenge is often a long-lasting endurance challenge, giving the remaining castaways time to make bargains and last-minute deals to get into the final Tribal Council. Typically, before this challenge, a "Rites of Passage" ceremony is held in which the remaining castaways pay tribute to each of the previously eliminated players in turn.[4]

Tribal Council is a specially built stage located near the tribe camps; tribes sit across a fire pit from the host, while the jury members, if present, sit off to the side. A small voting alcove adjoins the structure. Events at Tribal Council are presented as the finale of each episode.

The first time a tribe attends Tribal Council, its members are each given a torch and told to light it from the fire pit, with the statement that "fire represents your life in this game". If each person from a former tribe has never been there before after the merge, then he/she is given the opportunity to get the torch and light it. After the tribe is seated, the host will call in the jury (if in the Jury phase), reminding them they are there to watch but not speak. The host will then proceed to ask the tribe questions regarding camp life and events he witnessed at the challenges over the last few days. During this process, internal strife within the tribe may be brought to light, and castaways in precarious situations may reveal information or bargain with others to keep themselves in the game. Though only a few minutes of these proceedings are shown to the viewing audience, some Tribal Councils have gone on for hours.

Subsequently, the host will ask the tribe member with the immunity necklace if they want to keep it or transfer it to someone else; whoever wears it after this possible exchange cannot be voted for. The host then asks each castaway to make their vote in the alcove. The castaway is given an opportunity to speak to a camera in a message directed to the person they are voting off and to the viewers before placing the vote in an urn. When all votes are made, the host collects the urn, tallies the votes and starts reading the votes one by one. When enough votes have been read to eliminate one player, all remaining votes are kept secret (although in most cases it is assumed that any left over vote are to the eliminated player), and that player is asked to bring the host their torch, who then snuffs it out. The player is then told "the tribe has spoken" and is instructed to leave the Tribal Council area. The remainder of the tribe is then allowed to return to camp with their torches, though in some seasons, if they have not earned or made fire yet, they have been required to douse their torches before leaving; in All-Stars seasons, any tribe(s) that have not earned or made fire yet have been asked to leave their torches at Tribal Council.

The eliminated player is given the opportunity to speak to a camera about their feelings of being eliminated before they are secluded with other eliminated castaways until the end of filming. Those players that will become jury members are sequestered until the end of the final Tribal Council, and are not allowed to discuss their voting or issues with the remaining contestants, other jury members, or the final players, in order to prevent any possible cooperation or collusion from subgroups within the jury.

Ties may occur. Normally, a second vote is held, with only the tied players eligible to be voted for. If this second vote does not break the stalemate, a tie breaker is used, the nature of which has changed throughout the seasons. The first tie breaker, used in The Australian Outback season, took into consideration the number of votes each of the tied players had accumulated in previous Tribal Councils, and the player with the most previous votes was eliminated. When this tie breaker was used again, in the Africa season, both players had an equal number of previous votes, so a trivia quiz involving questions about Africa was used to determine the winner, and the loser was eliminated from the game. In subsequent seasons, the tie-breaker mechanism has been a random drawing in which each player except those with immunity must draw a rock from a bag, and the player with the single purple rock is eliminated. The first time this mechanism was used was during the Marquesas season's "final four" Tribal Council. Host Jeff Probst later announced that using this tie breaker during the final four tribal council had been a mistake, and that it should only be used when six or more players are involved. .[5] Since that season, while tribe members have occasionally considered deliberately creating a stalemate and allowing the purple rock tie-breaker to decide who goes home, they have tended to favor avoiding tie votes that would subject each of them to the risk of being randomly eliminated. When a tie has occurred with only four or fewer players left in a tribe, the tie breaker has been a challenge, which to date has always involved a race to be the first to build a small fire high enough to burn through a rope. The rock-drawing tie breaker was played again in Blood vs. Water; in this case, after reaching the first tie from voting, those that were not voted for had a brief period to come to a consensus of who to vote off or would otherwise have to draw rocks (black with one white rock) if they were not already immune.

The Final Tribal Council occurs when there are only two—or in later seasons three—players left in the game. The move to three final players was made so that the endgame would present more of a challenge to the castaway who wins the final immunity challenge: while that person is assured of being at the Final Tribal Council, they are not able to decide alone which of the other remaining castaways they will compete against for the jury's votes.[6] At the Final Tribal Council, each remaining castaway is given time to make a statement to the jury. Then each jury member in turn addresses them, asking each a question or commenting on their behavior in the game in an effort to sway the other jury members; the castaways are free to respond to these as they see fit. The remaining castaways may be given time for a concluding speech. After this, the host has each jury member in turn go to vote in the alcove, this time for the person that they feel should be named the Sole Survivor. As with regular elimination votes, the jurors are given an opportunity to speak to the camera to explain their vote. The host then collects the urn, and in most seasons, holds on to it for a live reading of the votes on the season's final show where the Sole Survivor is announced. No tie vote for Sole Survivor has ever occurred. although in many seasons it has been a theoretical possibility. The juries that have chosen between only two finalists have in most cases had an odd number of members, making a tie vote impossible. Probst has said that the producers have a contingency plan to be used in case of a future tie, reportedly involving a "white envelope," but the exact nature of this tie breaker has not been made known.[7]

Some players have been eliminated from the game by other means. Castaways who suffer severe injuries or exhaustion are evaluated by the medical team which is always on call. The medical team may provide treatment and give the player the option to continue in the game, warning them of the health risks involved. However, if the medical doctor determines that the player is at risk of permanent injury or death and needs to be removed from the game for their own health, they will be removed and taken to a nearby hospital. Occasionally, castaways who are not in need of medical treatment have decided to quit the game, without waiting to be voted out, due to physical or emotional exhaustion—either by making an announcement at a Tribal Council, in which case they are let out of the game without any vote, or by being recovered from camp after talking with others and being interviewed by the host. When a player leaves the game without being voted off, the other tribes are notified of the departed player's removal, and the next Tribal Council may be cancelled. After the players merge into one tribe, any who have been removed from the game by medical evacuation are still eligible to participate as jury members once the medical examiners deem them healthy enough to do so. Those that have quit the game voluntarily may also still be eligible for the jury, or they may instead be replaced by a player that was voted off earlier, and, if their reasons for leaving are considered sufficient, they may also still be allowed to make a farewell speech to the camera.

Hidden immunity idols are pocket-sized necklaces made to fit the theme of the season—that are hidden around the tribes' camps or other locations that the castaways have access to. When a castaway finds one of the idols, they have the option of concealing the fact that they have it, or strategically revealing the fact to other castaways. The idols can provide a one-time immunity to a castaway at Tribal Council, if played—which they can be, typically, anytime before the third-to-last Tribal Council. For example, they can be played during the tribal council of the final five castaways in a season where the final tribal council will consist of three players. The rules for playing the idol have changed during the seasons. In the first season where hidden idols were used, Guatemala, the rules provided that the idol must be played before the vote; other players could not vote for that player. Later, in Panama and Cook Islands, the idol could be played after the votes were read, nullifying the votes for that player; whoever received the next-highest number of votes was then eliminated. Beginning in Fiji and in all subsequent seasons, the idol has had to be played after the votes are cast, but before they are read. If it is played, any votes cast for that player do not count. This rule forces both the voters and the player with the hidden immunity idol to make a more complicated strategic decision: the voters may have to vote without knowing whether the person they are voting for has a hidden immunity idol, or without knowing whether that person will choose to play it, and the person with the idol must decide whether to play it without knowing whether enough votes have been cast to vote them out of the game. Sometimes, a player plays the idol and it turns out someone else got more votes, in which case the idol has been wasted. Other times, a player feels safe and decides not to play the idol, intending to save it to use at a later time, but ends up getting voted out and leaves the game with the idol unplayed. According to Probst, this latest version of the rules for using hidden immunity idols has proven to be a "happy medium" relative to the two previous versions.[8] While this idol returned for Survivor: Cagayan, an additional idol that functioned under the same rules as in Panama and Cook Islands was also introduced at the merge, but with the stipulation that it could only be used by the player who found it.[9]

The idol, once found by a player, cannot be stolen from them, but other castaways can look through their possessions to see if they have it. Sometimes a castaway who has an idol re-hides the idol in a location known only to them, to avoid the risk that others will find out they have it. The idol can be willingly transferred to another player at any point in the game, including at Tribal Council; in such cases, the castaway receiving the idol can play it to protect themselves.[10] Idols, once played, may be returned to the game after being hidden at a new location. When a castaway is blindsided and voted out of the game while in possession of an idol without having played it, the idol is considered to have left the game, and is not replaced. Castaways have used the idol as a bargaining chip to align other players with them and swing pending votes in a specific direction; as a result, some players have been inspired to create fake hidden immunity idols, and either leave them the spot that the original idol was found, or carry them around, bluffing with the fake idol to attempt to alter people's voting strategies in advance of Tribal Council. If a fake idol is played at Tribal Council, the host notes that it is not the real idol and destroys it by throwing it in the fire. In the U.S. version of the show, the producers have decided that the fake idol strategy adds an interesting twist, and have therefore quietly provided materials, such as beads and paint, through normal props within the game, to better enable players to make these fake idols.[11]

To help castaways find the idol, a series of clues are given to them in succession in a number of different ways. A clue may be given to the winner of a reward challenge, hidden among the reward prizes, announced by the host to all remaining castaways, or provided to a castaway who has been sent to Exile Island or temporarily sent to live with the other tribe. Castaways are under no obligation to share the idol clues with other players. Clues continue to be provided even after a player has secretly found the idol. Each successive clue includes all the previous clues given for that location. Only once an idol has been played, at which point the producers hide a new idol in a new location, are new clues provided to the players. Clues may lead to a location on Exile Island or back at the tribes' camps. In later seasons, players have been very aware that hidden idols may be in play from the start of the game and some have started to look for them near apparent landmarks before any clues have been provided. One castaway, Russell Hantz, was able to find six idols during his three appearances on the U.S. version of the show without the aid of clues. In light of this so-called "Russell factor," producers subsequently began hiding the idols in more difficult-to-find locations.[12]

Exile Island is a remote location away from the tribal camps, where one or two castaways are sent to live in isolation from the rest of their tribe. Exile Island was first introduced in Survivor: Palau, when a single contestant was made to stay alone on a beach for a day as a result of being the first to drop out of an Immunity Challenge. This twist would not be used regularly until Survivor: Panama; it was also used in Cook Islands, Fiji, Micronesia, Gabon, Tocantins, and San Juan del Sur.

A selected player is exiled to a location (typically a small island) apart from the main tribe camps. Typically, the castaway is exiled after the reward challenge, leaving the challenge location for Exile Island, and usually returns immediately before the following immunity challenge. The exiled castaway is chosen as a result of the reward challenge: in the tribal phase, a member of the losing tribe is exiled (usually exiled by the winning tribe), while in the individual phase, the reward challenge winner holds the sole right to choose. Unless stated otherwise, players who win the right to decide who goes to Exile Island may also choose to go themselves. In Micronesia, Tocantins, and San Juan del Sur, one person from each tribe was sent to Exile Island. Whenever there is a tribe shuffle with an uneven number of contestants, as in Panama, Fiji, and Gabon, the leftover contestant will be treated as "tribeless" and sent to Exile Island immediately after formation. In this case, the contestant will return and join the tribe that loses the next immunity challenge.

Once selected, the exiled contestant is immediately sent there. They are given minimal survival tools, typically a water canteen, a machete, a pot, and a limited amount of shelter. The two main disadvantages of being on Exile Island are the lack of food and water, which can weaken a player and make them less effective in challenges, and the isolation from other contestants, which can cause a player to become out of the loop and weaken their position in their tribe. Contestants are often sent to Exile Island for one or both of these strategic reasons.

The exiled castaway receives a consolation prize: in all seasons with Exile Island, the exiled castaway receives a clue to the hidden immunity idol, which may or may not be located on the island. On Survivor: Gabon, the exiled castaway was given the option to give up their idol clue for "instant comfort," and in Survivor: Tocantins, the exiled castaway had the right to change tribes. Occasionally, the exiled castaway is instructed to return after the next Tribal Council, earning them automatic immunity.

Two seasons of the U.S. version have used different variations on the Exile twists. In China, tribes who win reward challenges earned the right to "kidnap" a member of the losing tribe, and that person would have to stay with them until the next immunity challenge. The kidnapped person would be given a clue to the hidden immunity idol which he or she must give to one member of the winning tribe. In Samoa, a reverse version of the kidnapping rule was used, called "spy expedition" (also known as "observing"). The winning tribe would have to send one of their own to accompany the other tribe until the immunity challenge. Both of these twists were retired after the merge.

Redemption Island is a twist introduced on Survivor: Redemption Island and also used on Survivor: South Pacific and Survivor: Blood vs. Water. Redemption Island is a combination of the outcast twist from Survivor: Pearl Islands and Exile Island. After being voted out, contestants will remain in the game and are sent to Redemption Island. There, they will fend for themselves like the castaways in the game proper until the next person is voted out. The day following Tribal Council, there is a duel where the winner remains on the island and the losers are eliminated for good; upon elimination, the duel loser(s) must remove their buff and throw it into a small fire pit.

Double elimination cycles, or any other disruption of the game's pattern, leads to three or four duelists instead of two. In Survivor: Redemption Island only the loser of the duel was eliminated, resulting in eight people still being in the game at the finale (four in the main game, and four in Redemption) due to two double elimination cycles, with two Tribal Councils and no duels. Jeff Probst admitted that this was a bit much, and for Survivor: South Pacific, the rules were changed so only the winner remained in the game while all others were eliminated.

At the merge, the person remaining in Redemption is entered back into the game and the twist is reset. Then, when four people remain in the main game, the winner of the Redemption duel returns to the game, and Redemption Island is retired.

Redemption Island was reintroduced for Survivor: Blood vs. Water and adapted to fit with the loved one twist. On Day 1, when the tribes were initially assembled, both tribes were immediately forced to vote someone to Redemption Island. Prior to any duel, the castaways with loved ones on Redemption Island are given the choice to replace their loved one on Redemption Island, with their loved one returning to the main game and taking their place in the tribe. In addition, the first place winner of the duel must give a clue to a hidden immunity idol to any castaway in the main game.

An alternate version of Redemption Island was used in the first season of Survivor South Africa, when eliminated contestants were exiled to Dead Man's Island and later given a chance to come back into the game. Dead Man's Island was known for its tough conditions and atmosphere of despair, as contestants had to survive there without real purpose until near the end of the game.

The Sole Survivor receives a cash prize of $1,000,000 prior to taxes,[13] and sometimes also receives a car provided by the show's sponsor. Every player receives a prize for participating on Survivor depending on how long he or she lasts in the game. In most seasons, the runner-up receives $100,000, and third place wins $85,000. All other players receive money on a sliding scale, though specific amounts have rarely been made public. Sonja Christopher, the first player voted off of Survivor: Borneo, received $2,500.[14] In Survivor: Fiji, the first season with tied runners-up, the two runners-up received US$100,000 each, and Yau-Man Chan received US$60,000 for his fourth-place finish.[15] All players also receive an additional $10,000 for their appearance on the reunion show.[16]

Most seasons between The Australian Outback and Fiji have featured a late-season reward challenge where the winner receives a car. This reward was infamous for what was later dubbed the "car curse,"[17] referring to the fact that no player who ever won the car went on to win the game.

During the 2005 season the tribes were initially divided up by age into "Old" and "Young", with the old contestants being forty and older and the young contestants being under the age of thirty. This twist was later used during Survivor: Nicaragua and Robinsonekspedisjonen 2009.

During the pre-merge portion of the 2006 season two former contestants returned to the game to lead the tribes. As leader they were allowed to give individual immunity to any member of their tribe when they went to tribal council. Neither of these two contestants were eligible to win and both left shortly before the merge.

When there were only three contestants left during the 2006 season all of the contestants that had lost on "Losers Island" voted to eliminate one of the finalists.

The 2007 season began with one hundred contestants. Because many of these contestants weren't on the show for more than a couple of episodes many of their surnames are unknown.

When it came time to reveal the winner of the 2008 season it was revealed that the jury vote was tied at 3-3. This led to seventy four former contestants voting for a winner.

During the 2009 season the two tribes were initially composed of only women while a smaller tribe of men were hidden on a secluded beach. The men eventually entered the main competition in episode four. A similar twist was later used during Robinson 2011.

The 2014 run saw the introduction of a 3-way tribe contest: Heaven, Earth and Hell. Hell being placed in the middle of the mangrove bush. During the first episodes the losing tribe would vote off a member and relocate to Hell.

In every season of Koh-Lanta, just before the tribe merge, an ambassador is chosen in each tribe. Through season 8, they had the power to give one more vote to any contestant for the first Tribal Council of the merged tribe. In season 9 and later seasons (including the two All-Stars seasons), they were able to directly eliminate a contestant. However, if none of the ambassadors agree to vote for/eliminate one contestant, they must draw one pearl from a bag. The one who gets the black pearl loses and either gets a vote, or is directly eliminated depending on the season.

During season 3 (Bocas del Toro), the oldest man and woman had the option to choose the composition of their respective tribes, as long as gender parity was respected.

During season 4 (Panama), the two tribes were divided by gender. However, after 8 days, the tribes were mixed. A variation was used during season 10 (Vietnam), where the tribes were divided by gender except that one person per tribe was of the opposite gender.

During season 7 (Palawan) and season 8 (Caramoan), there was a challenge before the tribes' composition was decided: the best man and woman got the privilege to decide on the composition of their tribes, while the last man and woman were directly eliminated. The latter rule was also applied in season 9 (Palau) and in the first All-Stars season.

During the second All-Stars season, seven previous contestants were part of one tribe, while the other tribe was composed of famous French sportsmen.

In season 11 (Raja Ampat), two new rules were introduced: the hidden immunity idol, known from its appearance in the US version, and a new rule called the "vote noir" (black vote). After a contestant gets voted out at the Tribal Council, he or she can vote one more time against one of the remaining contestants of his or her tribe before quitting the game. This vote is counted at the tribe's next Tribal Council.

The third All-Stars season featured sixteen former contestants who, despite their performances, hasn't previously become the Sole Survivor.

In season 12 (Malaysia), four contestants out of the starting 20 won't initially be part of either of the two starting tribes. Instead, they will be on a version of "Exile Island", and will need to prove themselves in order to be integrated into one of the two tribes. Also, for the first time in the history of the program, two contestants will be eliminated at once in a single Tribal Council.

Due to an accidental death during the first day of shooting season 13, those in charge of producing the show decided to cancel the 2013 season. Following a fierce discussion of these events in the media regarding the medical conditions, the show's doctor took his own life. However, this didn't stop the show entirely, coming back in 2014 with a fourth all-stars season.

During the 2008 season the tribes were composed of fans of Robinson Ekspeditionen and former contestants from Paradise Hotel.

During the 2009 season the tribes were initially divided into "Smart" and "Dumb" based on the results of an IQ test the contestants took prior to the start of the competition.

During the 2010 season the contestants took part in a challenge that would ultimately divide them into "Masters" and "Slaves" within their own tribes (one tribe was composed of male masters and female slaves while the other was composed of female masters and male slaves).

Because a representative from each participating country was necessary for the finale, the last remaining member of each tribe was immune from all remaining eliminations.

In all seasons of Baltic Robinson the jury would vote for who they didn't want to win as opposed to who they did. These votes would be added along with those given to the losers of plank (in all seasons) and those of the public (in the first two seasons) or of the finalists (in season 3).

Introduced the "Double-Power Challenge" in Survivor 10: The Caribbean. The double-power challenge is an individual challenge, which is played after the Immunity challenge. Every person going to Tribal Council had to compete, and the winner of the challenge won an additional power at Tribal Council.

Introduced the "Veto Armlet" in Survivor 10: Pearl Islands. Aside from the Immunity Challenge, where the winner of the challenge wins the immunity, the Israel version introduced the Armlet Veto, wherein the winner of the Veto Challenge gets the armlet. The Veto Armlets purpose is to cancel the vote of a castaway.

In November 2011 it was announced that the 2012 season of Robinsonekspedisjonen will be known as "Robinson: Vinter" (Robinson: Winter) and it will be the first ever season of Robinson or Survivor to ever take place in a cold climate as it will be filmed in Norway.

Introduced the "Cursed and White Pearls", both roughly the size of a standard billiard ball. During the merge stage, the person voted out, before having his/her torch snuffed out, will receive either one or both of the Pearls and give each Pearl to one of the remaining castaways. The castaway who receives the Cursed Pearl gets one vote in the following Tribal Council. In case the Cursed Pearl is lost, the holder would then receive two votes. In-show, the Cursed Pearl is called the "Black Pearl" (though in the first season, its actual color is really silver). On the other hand, the White Pearl will have one vote subtracted from the count in the receiver's favor in the next Tribal Council, should at least one such vote comes up. This was introduced in the first season of Survivor Philippines.

Introduced the "Blood Pearl" in Survivor Philippines: Palau. The Blood Pearl served the same purpose as the Cursed Pearl, only, the holder would receive two votes in the next Tribal Council. In case the Blood Pearl is lost, three votes would be counted against the holder.

Introduced the Isla Purgatorio, which is called the Redemption Island in US version.

Introduced the "doubles format" in Survivor Philippines: Celebrity Doubles Showdown, wherein castaways are grouped as couples with preexisting relationships. In this format, the couple is treated as one castaway, wherein both members get immunity after winning Immunity Challenges, both win the reward from the Reward Challenges, and both are voted out in the Tribal Council.

Also in Survivor Philippines: Celebrity Doubles Showdown, the "Temptation Reward" was introduced. The winning tribe in a Reward Challenge would choose one or two of their own to be the only one/s partaking in the Temptation Reward. After being shown the Temptation Reward, the chosen one/s were then also presented with the consequence that comes upon accepting the Temptation Reward. Declining from the Temptation Reward is also an option, if those chosen would deem accepting it be too harmful for their life in the game.

During the 1999 season the twist of "The Black Vote" was introduced. During the merge portion of the competition whenever someone was voted out before they left tribal council they would cast one more vote. This vote would then be carried over to the next tribal council and whoever received the vote, assuming they didn't have immunity, would have an extra vote against them.

During the 2002 season when a contestant was voted out they were sent to a secret island where they would take part in a duel with another eliminated contestant. The contestant who lost said duel would be eliminated for good while the winner remained on the island. The person still inhabiting the island when there were only three contestants left in the game would re-enter the competition. This twist would later be used in several different versions of the show and has recently been used on Survivor: Redemption Island and Survivor: South Pacific.

During the All-Stars version of Expedition Robinson the tribes were initially divided into two tribes, one composed of "Veterans" and the other of "Fans". This type of twist was also used in the American version of Survivor during Survivor: Micronesia.

During the 2004 season the twist known as "Team X" was introduced. Shortly after the competition began a new group of contestants entered the game and lived separately and secretly away from the other contestants until a certain point in the game. This twist has since also been used in Norway's 2009 season.

During the 2004 and 2005 seasons a former contestant entered the game. This twist has since been used in many different Survivor versions around the world.

During the 2005 season the tribes were initially divided up into a "Rich" tribe and a "Poor" tribe. This twist has since been used in the Danish, Norwegian, and American versions, most notably in Survivor: Fiji.

Twists with unknown origins

During the year 2002 several different versions of Survivor used the twist of gender based tribes as a main twist for their seasons. Due to the fact that at the time the Baltic, Belgian/Dutch, Danish, Norwegian, and Swedish seasons were all traveling together in order to conserve and pool their resources, there is no way to determine which production team came up with the idea of the twist (though it's unlikely to be the Baltic's or Norway's as neither edition has ever used this twist). The same twist was used a few months later in 2003 during Survivor: Amazon and a couple years later in 2004 during Survivor: Vanuatu.

Conspiring to split winnings will result in immediate expulsion from the game.

Except for the occasional challenges which involve wrestling or limited combat, any physical violence between players will result in immediate expulsion from the game.

At Tribal Council, players are not permitted to vote for themselves, nor can they spoil their ballots or decline to cast a vote. Players must also show whom they voted for to the camera inside the voting booth.

Contestants must abide by U.S. law as well as local law. Breaking any of these laws will result in immediate removal from the game.

A regular hidden immunity idol can be played after the votes have been cast but before they are read.

A special hidden immunity idol can be played after the votes are read.

Hidden immunity idols cannot be stolen by another player.

If a contestant plays the hidden immunity idol, any votes cast for that contestant will not count, and the person with the next largest number of votes will be eliminated.

Tribe members may not raid or visit the campsite of another tribe unless they are doing so as part of an immunity challenge, reward challenge or tribal merger activity with the other tribe. They also may not visit the TV crew compound. Exceptions to this rule have been made, though, as a result of accident (as seen in Survivor: Cook Islands) or challenge victories. In Survivor: Guatemala one tribe intentionally visited the other to invite them over to lounge in their lake pool.

If a contestant becomes seriously injured or sick, the player, fellow contestants, the host, or even the crew filming the players may call in a medical team for help. In some cases, the player can be treated at their camp, but the player may also be deemed unable to participate further by the medical team and then be taken from camp to a medical facility, and removed from the game. Often, the players may decide for themselves whether their health will allow them to continue.

Contestants deciding to quit the contest for any reason not health - or other-emergency-related may or may not be called back for the final jury, pending the producers' decision, and may or may not get their closing speech aired, if their reasons are sufficient enough. (This rule was added after the end of Survivor: Nicaragua.) If a player decides to quit prior to Redemption Island, they are allowed to keep their buff instead of throwing it in the fire pit upon exiting (as was the case in Survivor: Blood vs. Water).

Depending on which country the show takes place in, contestants may be barred from killing local wildlife.

^1 The German Survivor created their own version after airing a co-production of Austrian-German Survivor in season 1. Austria had not continued its own series nor co-produced an Austrian-German Survivor after season 1.^2 Expedition Robinson 2005 (VIP) was a pan-regional version of Denmark, Norway, and Sweden.^3Survivor: Greece vs. Turkey is a co-production between the Greek and Turkish Survivor franchises. It was the third season of the popular show Survivor to air in Greece and the second season to air in Turkey. This was the first time that either country's franchise competed with another country and because of this the major twist this season was that the tribes were divided up by country of origin.^4 Is a season co-produced by the Croatian and Serbian franchises. It was the second season of Survivor to air in Croatia and the fourth season to air in Serbia.

One of the more novel merchandising items has been the interactive Survivor: The Ride thrill ride at California's Great America in Santa Clara, California. The ride includes a rotating platform on which riders are divided into one of four "tribes." As the ride moves along an undulating track, riders can be sprayed by water guns hidden in oversized tribal masks while drums and other familiar Survivor musical accents play in the background. Other theming includes Survivor memorabilia throughout the queue line and other merchandise for sale in nearby gift shops.[20] The ride has since been rethemed as Tiki Twirl.

During the first Survivor seasons many online games based on forums were created. More specific Survivor online games appeared later.

In late 2013, a former contestant of the American version of the show, Erik Reichenbach, launched a Kickstarter campaign for a Survivor-styled online mobile app called "Islands of Chaos". It pits players from all over the world in a battle of challenges and strategy to be the last one standing. If the campaign is successful, the plan is to release the game free of charge on a range of platforms including on Apple and Android devices.[21]

Beginning on July 8, 2007, a parody of Survivor called Total Drama Island appeared on the television network "Teletoon". This animated show included 22 summer campers who signed up to stay at a 5-star resort, which actually turned out to be a cruddy summer camp on an island somewhere in Muskoka, Ontario. The host, Chris McLean, is modeled after Survivor host Jeff Probst. The campers are taken to the island on boats to meet their fellow competitors, being heartbroken at the sight of their wasted summer. The campers were separated into two teams: The "Screaming Gophers" and the "Killer Bass". Every three days there would be a challenge for the campers to face, from jumping off a 1,000-foot high cliff into a lake to survival skills. The losing team of each challenge would go to the Bonfire Ceremony the night of the challenge, and vote someone off the team, like Survivor. Each team member still in the game would receive a marshmallow, leaving one team member without one. The member who does not receive a marshmallow (the symbol of life on the island) would have to walk the Dock of Shame and board the Boat of Losers to leave the island, and "Never ever ever ever ever" return (which turned out to be a lie in the episode "No Pain, No Game"). After 12 members of the island were voted off, the teams were merged. Two competitors were brought back into the game for another chance at the grand prize, C$100,000. When only three members are left, there is a sudden-death challenge. The person who does not accept a dare is immediately taken off the island. For the final challenge, the 20 campers voted off the island are brought back to root for one of the two survivors. The winner receives a check for the C$100,000 and the final marshmallow. The show then ends with Chris thrown off the Dock of Shame. The show aired in 188 countries and also appeared on the channels of Cartoon Network and Jetix. The show became a critical and commercial success and it spun off into a series.